Amount and type of protein influences bone health

Abstract

Many factors influence bone mass. Protein has been identified as being both detrimental and beneficial to bone health, depending on a variety of factors, including the level of protein in the diet, the protein source, calcium intake, weight loss, and the acid/base balance of the diet. This review aims to briefly describe these factors and their relation to bone health. Loss of bone mass (osteopenia) and loss of muscle mass (sarcopenia) that occur with age are closely related. Factors that affect muscle anabolism, including protein intake, also affect bone mass. Changes in bone mass, muscle mass, and strength track together over the life span. Bone health is a multifactorial musculoskeletal issue. Calcium and protein intake interact constructively to affect bone health. Intakes of both calcium and protein must be adequate to fully realize the benefit of each nutrient on bone. Optimal protein intake for bone health is likely higher than current recommended intakes, particularly in the elderly. Concerns about dietary protein increasing urinary calcium appear to be offset by increases in absorption. Likewise, concerns about the impact of protein on acid production appear to be minor compared with the alkalinizing effects of fruits and vegetables. Perhaps more concern should be focused on increasing fruit and vegetable intake rather than reducing protein sources. The issue for public health professionals is whether recommended protein intakes should be increased, given the prevalence of osteoporosis and sarcopenia.Am J Clin Nutr 2008;87(suppl):1567S-70S.

Dietary Protein Supplementation Increases Peak Bone Mass Acquisition in Energy-Restricted Growing Rats

“…Actually, it seems that whether dietary protein has a beneficial or detrimental effect on bone also depends on additional nutritional factors, such as calcium intake. An adequate calcium supply, as in this experiment, was suggested to erase the negative effect of protein on bone mass (26). Nevertheless, it remains possible that a diet substantially higher with reduced calcium intake in protein will cause deleterious effects on bone.…”

Whey Protein Supplementation and Higher Total Protein Intake Do Not Influence Bone Quantity in Overweight and Obese Adults Following a 36-Week Exercise and Diet Intervention

“…In contrast to the 2 previous studies (51,57), the present studyÕs population was composed of middle-age overweight and obese adults who were on average 50 y of age. With evidence showing an increase in IGF-I concentrations (50,51,57), intestinal calcium absorption (21,22), and the retention or improvement in BMD (10,(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43), increasing WP supplementation and/or TPro during this period of rapid bone loss could differentially influence bone metabolism and provide a more measurable change in bone quantity in comparison with older adults in whome the rate of bone loss has decreased (61). Furthermore, in contrast to the 2 previous studies (51, 57), higher concentrations of fat mass in the current studyÕs population provide a metabolically different environment, which not only influences bone metabolism via increased concentrations of leptin (62) and inflammatory cytokines (63) but potentially the effects of WP supplementation and/or TPro on bone quantity.…”

“…) are still actively debated and may be dependent on a number of factors, including quantity and source of dietary protein, calcium intake, energy balance (10), and physical activity (11). The acid-ash hypothesis (12) theorizes that the consumption of excess dietary protein acidifies the environment surrounding bone, through the oxidation of sulfur-containing amino acids and phosphoproteins, leading to bone demineralization (8,13), diet-induced hypercalciuria (14,15), and a negative calcium balance (16)(17)(18).…”

“…Different sources of dietary protein contain varying amino acid compositions as well as additional micronutrient, bioactive, and nonnutritive components, which collectively may differentially influence bone health (10,(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43). Whey protein (WP) is 1 of 2 proteins contained in dairy and is a commonly used protein supplement.…”

Optimal nutrition for bone health in people with a learning disability

“…Protein not only affords bones structural matrix but also stimulates IGF-1 to increase osteoblast activity and increases calcium absorption in the intestine (Heaney and Layman, 2008). Low protein diets have a negative additive effect with low calcium or low vitamin D status on skeletal integrity especially in postmenopausal women (Marotte et al, 2013).…”